<nav>
    <ul class="navigation-list">
        {% assign pages_list = site.html_pages | sort:"nav_order" %}
        {% for node in pages_list %}
        {% unless node.nav_exclude %}
        {% if node.parent == nil %}
        <li class="navigation-list-item{% if page.url == node.url or page.parent == node.title or page.grand_parent == node.title %} active{% endif %}">
            {% if page.parent == node.title or page.grand_parent == node.title %}
            {% assign first_level_url = node.url | absolute_url %}
            {% endif %}
            <a href="{{ node.url | absolute_url }}" class="navigation-list-link{% if page.url == node.url %} active{% endif %}">{{
                node.title }}</a>
            {% if node.has_children %}
            {% assign children_list = site.html_pages | sort:"nav_order" %}
            <ul class="navigation-list-child-list ">
                {% for child in children_list %}
                {% if child.parent == node.title %}
                <li class="navigation-list-item {% if page.url == child.url or page.parent == child.title %} active{% endif %}">
                    {% if page.url == child.url or page.parent == child.title %}
                    {% assign second_level_url = child.url | absolute_url %}
                    {% endif %}
                    <a href="{{ child.url | absolute_url }}" class="navigation-list-link{% if page.url == child.url %} active{% endif %}">{{
                        child.title }}</a>
                    {% if child.has_children and (page.url == child.url or page.parent == child.title) and  page.grand_parent == node.title %}
                    {% assign grand_children_list = site.html_pages | sort:"nav_order" %}
                    <ul class="navigation-list-child-list">
                        {% for grand_child in grand_children_list %}
                        {% if grand_child.parent == child.title %}
                        <li class="navigation-list-item {% if page.url == grand_child.url %} active{% endif %}">
                            <a href="{{ grand_child.url | absolute_url }}" class="navigation-list-link{% if page.url == grand_child.url %} active{% endif %}">{{
                                grand_child.title }}</a>
                        </li>
                        {% endif %}
                        {% endfor %}
                    </ul>
                    {% endif %}
                </li>
                {% endif %}
                {% endfor %}
            </ul>
            {% endif %}
        </li>
        {% endif %}
        {% endunless %}
        {% endfor %}
    </ul>
</nav>